1
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Sapre AA, Novitskaya E, Vakharia V, Cota A, Wrasidlo W, Hanrahan SM, Derenzo S, Makale MT, Graeve OA. Optimized Scintillator YAG:Pr Nanoparticles for X-ray Inducible Photodynamic Therapy. MATERIALS LETTERS 2018; 228:49-52. [PMID: 30505045 PMCID: PMC6258075 DOI: 10.1016/j.matlet.2018.05.090] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We describe a sol-gel synthetic method for the production of praseodymium-doped yttrium aluminum garnet (YAG) nanoparticles suitable for X-ray inducible photodynamic therapy (X-PDT). Our sol-gel based approach was optimized by varying temperature and time of calcination, resulting in nanoparticles that were smooth, spherical, and 50-200 nm in crystallite size. The powders were uniformly coated with a thin (10 nm) layer of silica to facilitate surface conjugation with functional moieties. Measurements of photon flux revealed that coated and uncoated powders emitted a similar photon emission spectrum in response to 50 keVp X-rays. We also determined that the presence of silica did not significantly reduce flux and the emission peak had a maximum at approximately 320 nm. Thus, these YAG:Pr powders are suitable candidates for future in vivo X-PDT studies.
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Affiliation(s)
- Ajay A. Sapre
- University of California, San Diego, Department of Bioengineering, 9500 Gilman Drive – MC 0412, La Jolla, CA 92093-0412, USA
| | - Ekaterina Novitskaya
- University of California, San Diego, Department of Mechanical and Aerospace Engineering, 9500 Gilman Drive – MC 0411, La Jolla, CA 92093-0411, USA
| | - Ved Vakharia
- University of California, San Diego, Department of Mechanical and Aerospace Engineering, 9500 Gilman Drive – MC 0411, La Jolla, CA 92093-0411, USA
| | - Alejandro Cota
- University of California, San Diego, Department of Mechanical and Aerospace Engineering, 9500 Gilman Drive – MC 0411, La Jolla, CA 92093-0411, USA
| | - Wolfgang Wrasidlo
- University of California, San Diego, Department of Neurosciences, 9500 Gilman Drive – MC 0662, La Jolla, CA 92093-0662, USA
| | - Stephen M. Hanrahan
- Lawrence Berkeley National Laboratory, Molecular Biophysics and Integrated Bioimaging Division, Cellular and Tissue Imaging Department, 1 Cyclotron Road, M/S 55-121, Berkeley, CA 94720, USA
| | - Stephen Derenzo
- Lawrence Berkeley National Laboratory, Molecular Biophysics and Integrated Bioimaging Division, Cellular and Tissue Imaging Department, 1 Cyclotron Road, M/S 55-121, Berkeley, CA 94720, USA
| | - Milan T. Makale
- University of California, San Diego, Department of Radiation Medicine and Applied Sciences, 3855 Health Sciences Drive #0819, La Jolla, CA 92093-0819, USA
| | - Olivia A. Graeve
- University of California, San Diego, Department of Mechanical and Aerospace Engineering, 9500 Gilman Drive – MC 0411, La Jolla, CA 92093-0411, USA
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2
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Siebert R, Winter A, Schmitt M, Popp J, Schubert US, Dietzek B. Light-Induced Dynamics in Conjugated Bis(terpyridine) Ligands - A Case Study Toward Photoactive Coordination Polymers. Macromol Rapid Commun 2012; 33:481-97. [DOI: 10.1002/marc.201100753] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Revised: 01/02/2012] [Indexed: 12/25/2022]
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3
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Rodríguez-Córdoba W, Sierra CA, Ochoa Puentes C, Lahti PM, Peon J. Photoinduced Energy Transfer in Bichromophoric Pyrene–PPV Oligomer Systems: The Role of Flexible Donor–Acceptor Bridges. J Phys Chem B 2012; 116:3490-503. [DOI: 10.1021/jp208602q] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- William Rodríguez-Córdoba
- Universidad Nacional Autónoma de México, Instituto de Química, Ciudad
Universitaria, 04510, México, D.F., México
| | - Cesar A. Sierra
- Universidad Nacional de Colombia, Departamento de Química,
Bogotá AA 14490, Colombia
| | | | - Paul M. Lahti
- Department of Chemistry, University of Massachusetts, Amherst, Massachusetts
01003, United States
| | - Jorge Peon
- Universidad Nacional Autónoma de México, Instituto de Química, Ciudad
Universitaria, 04510, México, D.F., México
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4
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Liu HW, Ngo AT, Cosa G. Enhancing the Emissive Properties of Poly(p-phenylenevinylene)-Conjugated Polyelectrolyte-Coated SiO2 Nanoparticles. J Am Chem Soc 2012; 134:1648-52. [DOI: 10.1021/ja208437e] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Hsiao-Wei Liu
- Department
of Chemistry and Centre for Self-Assembled
Chemical Structures (CSACS/CRMAA), McGill University, 801 Sherbrooke
Street West, Montreal, Quebec H3A 2K6, Canada
| | - An Thien Ngo
- Department
of Chemistry and Centre for Self-Assembled
Chemical Structures (CSACS/CRMAA), McGill University, 801 Sherbrooke
Street West, Montreal, Quebec H3A 2K6, Canada
| | - Gonzalo Cosa
- Department
of Chemistry and Centre for Self-Assembled
Chemical Structures (CSACS/CRMAA), McGill University, 801 Sherbrooke
Street West, Montreal, Quebec H3A 2K6, Canada
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5
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Burrows HD, Narwark O, Peetz R, Thorn-Csányi E, Monkman AP, Hamblett I, Navaratnam S. Mechanistic studies on the photodegradation of 2,5-dialkyloxyl-substituted para-phenylenevinylene oligomers by singlet oxygen. Photochem Photobiol Sci 2010; 9:942-8. [DOI: 10.1039/c0pp00053a] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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6
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Pina J, Seixas de Melo JS. A comprehensive investigation of the electronic spectral and photophysical properties of conjugated naphthalene–thiophene oligomers. Phys Chem Chem Phys 2009; 11:8706-13. [DOI: 10.1039/b909113k] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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7
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O'Neill L, Lynch P, McNamara M, Byrne HJ. Correlation of vibrational intensity with fluorescence lifetimes in π conjugated polymers. POLYMER 2008. [DOI: 10.1016/j.polymer.2008.07.035] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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8
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Farley RT, Zheng Q, Gladysz JA, Schanze KS. Photophysics of Diplatinum Polyynediyl Oligomers: Chain Length Dependence of the Triplet State in sp Carbon Chains. Inorg Chem 2007; 47:2955-63. [PMID: 17902651 DOI: 10.1021/ic701220t] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The series of polyynes with the structure trans, trans-[Ar-Pt(P 2)-(C[triple bond]C) n -Pt(P 2)-Ar], where P = tri( p-tolyl)phosphine, Ar = p-tolyl, and n = 3, 4, 5, 6 (6, 8, 10, 12 sp carbon atoms), has been subjected to a comprehensive photophysical investigation. At low temperature ( T < 140 K) in a 2-methyltetrahydrofuran (MTHF) glass, the complexes exhibit moderately efficient phosphorescence appearing as a series of narrow (fwhm < 200 cm (-1)) vibronic bands separated by ca. 2100 cm (-1). The emission is assigned to a (3)pi,pi* triplet state that is concentrated on the sp carbon chain, and the vibronic progression arises from coupling of the excitation to the -C[triple bond]C- stretch. The 0-0 energy of the phosphorescence decreases with increasing sp carbon chain length, spanning a range of over 6000 cm (-1) across the series. Transient absorption spectroscopy carried out at ambient temperature confirms that the (3)pi,pi* triplet is produced efficiently, and it displays a strongly allowed triplet-triplet absorption. In the MTHF solvent glass ( T < 140 K), the emission lifetimes increase with emission energy. Analysis of the triplet nonradiative decay rates reveals a quantitative energy gap law correlation. The nonradiative decay rates can be calculated by using parameters recovered from a single-mode Franck-Condon fit of the emission spectra.
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Affiliation(s)
- Richard T Farley
- Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
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9
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Chen HL, Huang YF, Hsu CP, Lim TS, Kuo LC, Leung MK, Chao TC, Wong KT, Chen SA, Fann W. Direct Measurements of Intersystem Crossing Rates and Triplet Decays of Luminescent Conjugated Oligomers in Solutions. J Phys Chem A 2007; 111:9424-30. [PMID: 17696510 DOI: 10.1021/jp0740651] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Photothermal calorimetry and fluorescence spectroscopy were used to determine the relaxations of the photoexcited singlet state of two PPV and polyfluorene oligomers, (E,E)-1,4-bis[(2-benzyloxy)styryl]benzene (PVDOP) and ter(9,9'-spirobifluorene) (TSBF). The decay rates of different S1 relaxation channels, which include intersystem crossing (ISC), radiative, and nonradiative decay can be determined by the combination of photoacoustic calorimetry (PAC) and the time-correlated single photon counting (TCSPC) technique. The triplet state energy level is determined by the phosphorescence (Ph) spectra recorded at 77 K. The ISC yields are approximately 3% and 6% for PVDOP and TSBF, respectively. The T1 to S0 transition decay rate is acquired by PAC and photothermal beam deflection (PBD) measurements. The triplet state decay rate is 17 and 21 ms(-1) at room temperature. The Ph intensity decay at 77 K shows that the triplet state lifetime increases by 4 orders of magnitude, as compared to room temperature.
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Affiliation(s)
- Hsin-Liang Chen
- Department of Physics, National Taiwan University, Taipei 106, Taiwan
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Okamoto K, Seki S, Tagawa S. Formation of trimer and dimer radical cations of methyl-substituted benzenes in gamma-irradiated low-temperature matrices. J Phys Chem A 2007; 110:8073-80. [PMID: 16805493 DOI: 10.1021/jp061527m] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Dimer and trimer radical cations of benzene, toluene, and xylenes were produced selectively after gamma-irradiation in low-temperature 2-methylpentane matrices with electron scavengers: oxygen (O(2)) and sec-butyl chloride (sec-BuCl). The charge resonance (CR) band of the trimer radical cation (M(3)(+)) produced via the corresponding dimer radical cation (M(2)(+)) is clearly seen in the solution containing O(2) as the temperature increases over a range from 80 to 90 K. In o-xylene solution, a fairly strong and distinct M(3)(+) CR absorption is observed; this is due to the large M(3)(+)/M(2)(+) relative extinction coefficient. All benzene derivatives show an equilibrium between dimer and trimer radical cations at approximately 90 K; however, the equilibrium constants of toluene and the xylenes are considerably lower than that of benzene. Formation of the trimer radical cation is inhibited in sec-BuCl, which has commonly been used as a low-temperature optical matrix for producing cationic species. An ab initio DFT method is applied to predict the geometry of M(3)(+), giving "slipped sandwich" (for benzene, m-xylene, and p-xylene) and "slipped fan-shaped" (toluene and o-xylene) structures as the most plausible geometries. The experimentally observed spectroscopic parameters reflect well those predicted by TD-DFT calculation based on geometry, suggesting strong dependence of the geometry of M(3)(+) on substitution patterns. This is the first report not only of direct spectroscopic observation of aromatic trimer radical cations in the condensed phase but also on the quantitative analysis of their equilibria.
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Affiliation(s)
- Kazumasa Okamoto
- The Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan
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11
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Seki S, Tagawa S. Optoelectronic Properties and Nanostructure Formation of σ-Conjugated Polymers. Polym J 2007. [DOI: 10.1295/polymj.pj2006222] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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12
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Jiu T, Li Y, Liu X, Liu H, Li C, Ye J, Zhu D. Molecular modeling of poly(p-phenylenevinylene): Synthesis and photophysical properties of oligomers. ACTA ACUST UNITED AC 2007. [DOI: 10.1002/pola.21862] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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13
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Seixas de Melo J, Pina J, Burrows H, Di Paolo R, Maçanita A. Electronic spectral and photophysical properties of some p-phenylenevinylene oligomers in solution and thin films. Chem Phys 2006. [DOI: 10.1016/j.chemphys.2006.09.016] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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14
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Fonseca SM, Pina J, Arnaut LG, Seixas de Melo J, Burrows HD, Chattopadhyay N, Alcacer L, Charas A, Morgado J, Monkman AP, Asawapirom U, Scherf U, Edge R, Navaratnam S. Triplet-State and Singlet Oxygen Formation in Fluorene-Based Alternating Copolymers. J Phys Chem B 2006; 110:8278-83. [PMID: 16623508 DOI: 10.1021/jp060251f] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Data are reported on the triplet states of a series of fluorene-based A-alt-B type alternating copolymers based on pulse radiolysis-energy transfer and flash photolysis experiments. From the pulse radiolysis experiments, spectra are given for eight copolymers involving phenylene, thiophene, benzothiadiazole, and oligothienylenevinylene groups. Quantum yields for triplet-state formation (PhiT) have been obtained by flash photolysis following laser excitation and in one case by photoacoustic calorimetry. In addition, yields of sensitized formation of singlet oxygen have been determined by time-resolved phosphorescence and are, in general, in excellent agreement with the PhiT values. In all cases, the presence of thiophene units is seen to increase intersystem-crossing quantum yields, probably because of the presence of the heavy sulfur atom. However, with the poly[2,7-(9,9-bis(2'-ethylhexyl)fluorene)-alt-1,4-phenylene] (PFP), thiophene S,S-dioxide (PFTSO2) and benzothiadiazole (F8BT) copolymers, low yields of triplet formation are observed. With three of the copolymers, the energies of the triplet states have been determined. With PFP, the triplet energy is virtually identical to that of poly[2,7-(9,9-bis(2'-ethylhexyl)fluorene)]. In contrast, with fluorene-thiophene copolymers PFaT and PF3T, the triplet energies are closer to those of thiophene oligomers, indicating that there is significant conjugation between fluorene and thiophene units but also that there is a more localized triplet state than with the homopolymers.
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Affiliation(s)
- S M Fonseca
- Departamento de Química, Universidade de Coimbra, 3004-535 Coimbra, Portugal
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15
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Pina J, Burrows HD, Becker RS, Dias FB, Maçanita AL, Seixas de Melo J. Photophysical Studies of α,ω-Dicyano-oligothiophenes NC(C4H2S)nCN (n = 1−6). J Phys Chem B 2006; 110:6499-505. [PMID: 16570947 DOI: 10.1021/jp055455v] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The photophysics of six oligothiophenes end-capped with cyano groups (CNalphan) was investigated in solution at room and low temperature. The study comprises singlet-singlet and triplet-triplet absorption and emission spectra together with lifetimes and quantum yields for all the radiative and nonradiative processes. From the lifetimes and quantum yields, it was possible to extract the rate constants for all the processes. Singlet oxygen yields were also determined, revealing an efficient sensitization (SDelta approximately 1) of its formation by the triplet state of the CNalphan. The introduction of the cyano groups is found to decrease the energetic separation between the highest occupied molecular orbital and the lowest unoccupied molecular orbital, leading to a red shift of the absorption and the emission when compared with the unsubstituted counterparts, the alpha-oligothiophenes. Phosphorescence is only observed for the first member of the series, CNalpha1.
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Affiliation(s)
- J Pina
- Departamento de Química, Universidade de Coimbra, 3004-535 Coimbra, Portugal
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Enomoto K, Laverne JA, Pimblott SM. Products of the Triplet Excited State Produced in the Radiolysis of Liquid Benzene. J Phys Chem A 2006; 110:4124-30. [PMID: 16539438 DOI: 10.1021/jp057153z] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The radiation chemical yields of the products derived from the triplet excited state produced in the radiolysis of liquid benzene with gamma-rays, 10 MeV 4He ions, and 10 MeV 12C ions have been determined. Iodine scavenging techniques have been used to examine the formation and role of radicals, especially the H atom and phenyl radical. For all irradiation types examined here, the increase in hydrogen iodide yields with increasing iodine concentration matches the increase in iodobenzene yields. This agreement suggests that the benzene triplet excited state is the common precursor for the H atom and the phenyl radical. Pulse radiolysis studies in liquid benzene have determined the rate coefficients for the reactions of phenyl radicals with iodine and with the solvent benzene to be 9.3 x 10(9) M(-1) s(-1) and 3.1 x 10(5) M(-1) s(-1), respectively. Direct measurements of polymer formation, which refers to trimers (C18) and higher order compounds (>C18), in liquid benzene radiolysis using gamma-rays, 4He ions, and 12C ions at relatively high doses have been performed using gel permeation chromatography. The yields of trimers increase from gamma-rays to 12C ions due to the increased importance of intratrack radical-radical reactions that can be scavenged by the radical scavenging reactions of iodine. On the other hand, the >C18 product yields decrease from gamma-rays to 12C ions. The structure of the polymer consists of a partly saturated ring as determined by infrared and gas chromatography/mass spectrometry studies. A schematic representation for the radiolytic decomposition of the benzene triplet excited state is presented.
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Affiliation(s)
- Kazuyuki Enomoto
- Radiation Laboratory and Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556, USA
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17
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Samori S, Tojo S, Fujitsuka M, Yang SW, Elangovan A, Ho TI, Majima T. Efficient Emission from Charge Recombination during the Pulse Radiolysis of Electrochemical Luminescent Donor−Acceptor Molecules with an Ethynyl Linkage. J Org Chem 2005; 70:6661-8. [PMID: 16095284 DOI: 10.1021/jo0506377] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Efficient monomer and excimer emission from various donor-acceptor substituted phenylethynes (PE), which are known as efficient electrogenerated chemiluminescent molecules, was observed with time-resolved fluorescence measurement during the pulse radiolysis in benzene. On the basis of the transient absorption and emission measurements, and steady-state measurements, the formation of PE in the singlet excited state (1PE*) and the excimer (1PE2*) can be interpreted by the charge recombination between the PE radical cation (PE.+) and the PE radical anion (PE.-) which are generated initially from the radiolytic reaction in benzene. It is suggested that the positive and negative charges are localized on the donor and acceptor moieties in the radical cation and anion, respectively. This mechanism is reasonably explained by the relationship between the annihilation enthalpy changes (-DeltaH' degrees ) and singlet excitation energies of donor-substituted phenyl(9-acridinyl)ethynes (1(a-e)). In addition to the monomer emission, the compounds bearing weak donors (1(a-d)) show the excimer emission due to a very small twist angle between the donor and acceptor moieties. For the phenyl(9-cyano-10-anthracenyl)ethynes (2(c) and 2(f)), although they also show the monomer and excimer emissions, it cannot be explained by the relationship between -DeltaH' degrees values and their singlet excitation energies, suggesting the formation of the ICT state and H-type excimer in which two 9-cyano-10-anthracenyl moieties are stacked face-to-face with donor bearing a benzene ring projecting perpendicularly away from each other through the charge recombination between 2.+) and 2.-) and/or triplet-triplet annihilation.
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Affiliation(s)
- Shingo Samori
- Institute of Scientific and Industrial Research (SANKEN), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567-0047, Japan
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18
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Samori S, Hara M, Tojo S, Fujitsuka M, Yang SW, Elangovan A, Ho TI, Majima T. Efficient Emission from Charge Recombination during the Pulse Radiolysis of Electrochemical Luminescent Substituted Quinolines with Donor−Acceptor Character. J Phys Chem B 2005; 109:11735-42. [PMID: 16852441 DOI: 10.1021/jp051340f] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Efficient emission from various donor-acceptor quinolines with an ethynyl linkage (PnQ), which are known as efficient electrogenerated chemiluminescent molecules, was observed with time-resolved fluorescence measurement during the pulse radiolysis in benzene. On the basis of the transient absorption and emission measurements, and steady-state measurements, the formation of PnQ in the singlet excited state can be interpreted by charge recombination between the PnQ radical cation and the PnQ radical anion which are generated initially from the radiolytic reaction in benzene. The strong electronic coupling between the donor and acceptor through conjugation is responsible for the efficient emission during the pulse radiolysis of PnQ in benzene. It is suggested that the positive and negative charges are localized on the donor and acceptor moieties in the radical cation and anion, respectively. This mechanism is reasonably explained by the relationship between the annihilation enthalpy changes and singlet excitation energies of PnQ. The formation of the intramolecular charge transfer state is assumed for PnQ in the singlet excited state with a strong electron donating substituent. The emission from PnQ is suggested to originate from PnQ in the singlet excited state formed from the charge recombination between the PnQ radical cation and the PnQ radical anion during the pulse radiolysis. This is strong evidence for the efficient electrogenerated chemiluminescence of PnQ.
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Affiliation(s)
- Shingo Samori
- The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567-0047, Japan
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Fratiloiu S, Candeias LP, Grozema FC, Wildeman J, Siebbeles LDA. VIS/NIR Absorption Spectra of Positively Charged Oligo(phenylenevinylene)s and Comparison with Time-Dependent Density Functional Theory Calculations. J Phys Chem B 2004. [DOI: 10.1021/jp046665v] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Silvia Fratiloiu
- Department of Radiation Chemistry, Interfaculty Reactor Institute, Delft University of Technology, Mekelweg 15, 2629 JB Delft, The Netherlands, Laboratory for Applied Inorganic Chemistry, Delft University of Technology, Julianalaan 136, 2628 BL, Delft, The Netherlands, and Department of Polymer Chemistry, Materials Science Center, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Luis P. Candeias
- Department of Radiation Chemistry, Interfaculty Reactor Institute, Delft University of Technology, Mekelweg 15, 2629 JB Delft, The Netherlands, Laboratory for Applied Inorganic Chemistry, Delft University of Technology, Julianalaan 136, 2628 BL, Delft, The Netherlands, and Department of Polymer Chemistry, Materials Science Center, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Ferdinand C. Grozema
- Department of Radiation Chemistry, Interfaculty Reactor Institute, Delft University of Technology, Mekelweg 15, 2629 JB Delft, The Netherlands, Laboratory for Applied Inorganic Chemistry, Delft University of Technology, Julianalaan 136, 2628 BL, Delft, The Netherlands, and Department of Polymer Chemistry, Materials Science Center, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Jurjen Wildeman
- Department of Radiation Chemistry, Interfaculty Reactor Institute, Delft University of Technology, Mekelweg 15, 2629 JB Delft, The Netherlands, Laboratory for Applied Inorganic Chemistry, Delft University of Technology, Julianalaan 136, 2628 BL, Delft, The Netherlands, and Department of Polymer Chemistry, Materials Science Center, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Laurens D. A. Siebbeles
- Department of Radiation Chemistry, Interfaculty Reactor Institute, Delft University of Technology, Mekelweg 15, 2629 JB Delft, The Netherlands, Laboratory for Applied Inorganic Chemistry, Delft University of Technology, Julianalaan 136, 2628 BL, Delft, The Netherlands, and Department of Polymer Chemistry, Materials Science Center, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
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20
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Oseki Y, Fujitsuka M, Hara M, Cai X, Sugimoto A, Majima T. Higher Triplet Excited States of Oligo(p-phenylenevinylene)s. J Phys Chem B 2004. [DOI: 10.1021/jp047275b] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yosuke Oseki
- The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567- 0047, Japan
| | - Mamoru Fujitsuka
- The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567- 0047, Japan
| | - Michihiro Hara
- The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567- 0047, Japan
| | - Xichen Cai
- The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567- 0047, Japan
| | - Akira Sugimoto
- The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567- 0047, Japan
| | - Tetsuro Majima
- The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567- 0047, Japan
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Seixas de Melo J, Pina J, Burrows H, Brocke S, Herzog O, Thorn-Csányi E. The effect of substitution and isomeric imperfection on the photophysical behaviour of p-phenylenevinylene trimers. Chem Phys Lett 2004. [DOI: 10.1016/j.cplett.2004.02.093] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Seki S, Koizumi Y, Kawaguchi T, Habara H, Tagawa S. Dynamics of Positive Charge Carriers on Si Chains of Polysilanes. J Am Chem Soc 2004; 126:3521-8. [PMID: 15025479 DOI: 10.1021/ja039840e] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The transient absorption of radical cations of a variety of substituted polysilanes is discussed quantitatively in terms of the molar extinction coefficient and oscillator strength by nanosecond pulse radiolysis. Oxygen-saturated polysilane solutions in benzene exhibit a strong transient absorption band ascribed to the polysilane radical cation. The transient species react with N,N,N',N'-tetramethyl-p-phenylene-diamine (TMPD) to produce TMPD radical cations. On the basis of the molar extinction coefficient of the TMPD radical cation, the molar extinction coefficients for the radical cations of polysilanes are found to increase in the range 3.3 x 10(4) to 2.0 x 10(5) M(-)(1) cm(-)(1) with increasing polymer segment length. The stepwise increase in the total oscillator strength with an increase in the number of phenyl rings directly bonded to the Si skeleton suggests the delocalization of the positive polaron state and/or the SOMO state over the phenyl rings, indicating the importance of phenyl rings in intermolecular hole transfer processes.
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Affiliation(s)
- Shu Seki
- Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan.
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Sarker AM, Kaneko Y, Lahti PM, Karasz FE. Excited States of Bromine-Substituted Distyrylbenzenes: Models for Conjugated Polymer Emission. J Phys Chem A 2003. [DOI: 10.1021/jp030041s] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ananda M. Sarker
- Department of Polymer Science & Engineering, and Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003, and Photonics Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, 305 Japan
| | - Yuji Kaneko
- Department of Polymer Science & Engineering, and Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003, and Photonics Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, 305 Japan
| | - Paul M. Lahti
- Department of Polymer Science & Engineering, and Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003, and Photonics Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, 305 Japan
| | - Frank E. Karasz
- Department of Polymer Science & Engineering, and Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003, and Photonics Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, 305 Japan
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Kawaguchi T, Seki S, Okamoto K, Saeki A, Yoshida Y, Tagawa S. Pulse radiolysis study of radical cations of polysilanes. Chem Phys Lett 2003. [DOI: 10.1016/s0009-2614(03)00740-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Candeias LP, Grozema FC, Padmanaban G, Ramakrishnan S, Siebbeles LDA, Warman JM. Positive Charge Carriers on Isolated Chains of MEH−PPV with Broken Conjugation: Optical Absorption and Mobility. J Phys Chem B 2003. [DOI: 10.1021/jp021656c] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Luis P. Candeias
- Department of Radiation Chemistry, IRI, Delft University of Technology, Mekelweg 15, 2629 JB Delft, The Netherlands, and Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560 012, India
| | - Ferdinand C. Grozema
- Department of Radiation Chemistry, IRI, Delft University of Technology, Mekelweg 15, 2629 JB Delft, The Netherlands, and Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560 012, India
| | - G. Padmanaban
- Department of Radiation Chemistry, IRI, Delft University of Technology, Mekelweg 15, 2629 JB Delft, The Netherlands, and Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560 012, India
| | - S. Ramakrishnan
- Department of Radiation Chemistry, IRI, Delft University of Technology, Mekelweg 15, 2629 JB Delft, The Netherlands, and Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560 012, India
| | - Laurens D. A. Siebbeles
- Department of Radiation Chemistry, IRI, Delft University of Technology, Mekelweg 15, 2629 JB Delft, The Netherlands, and Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560 012, India
| | - John M. Warman
- Department of Radiation Chemistry, IRI, Delft University of Technology, Mekelweg 15, 2629 JB Delft, The Netherlands, and Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560 012, India
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Grozema FC, Candeias LP, Swart M, van Duijnen PT, Wildeman J, Hadziioanou G, Siebbeles LDA, Warman JM. Theoretical and experimental studies of the opto-electronic properties of positively charged oligo(phenylene vinylene)s: Effects of chain length and alkoxy substitution. J Chem Phys 2002. [DOI: 10.1063/1.1522374] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Burrows H, Seixas de Melo J, Serpa C, Arnaut L, Miguel MG, Monkman A, Hamblett I, Navaratnam S. Triplet state dynamics on isolated conjugated polymer chains. Chem Phys 2002. [DOI: 10.1016/s0301-0104(02)00684-5] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Candeias LP, Padmanaban G, Ramakrishnan S. The effect of broken conjugation on the optical absorption spectra of the triplet states of isolated chains of poly(phenylene vinylene)s. Chem Phys Lett 2001. [DOI: 10.1016/s0009-2614(01)01172-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Burrows HD, Seixas de Melo J, Serpa C, Arnaut LG, Monkman AP, Hamblett I, Navaratnam S. S1∼>T1 intersystem crossing in π-conjugated organic polymers. J Chem Phys 2001. [DOI: 10.1063/1.1413969] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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31
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Photoinduced intermolecular electron transfer between oligo(p-phenylene vinylene)s and N-methylfulleropyrrolidine in a polar solvent. Chem Phys Lett 2000. [DOI: 10.1016/s0009-2614(00)00964-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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